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arXiv · 1209.2977

The Leggett-Garg inequality in electron interferometers

Clive Emary·Neill Lambert·Franco Nori
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Abstract

We consider the violation of the Leggett-Garg inequality in electronic Mach-Zehnder inteferometers. This set-up has two distinct advantages over earlier quantum-transport proposals: firstly, the required correlation functions can be obtained without time-resolved measurements. Secondly, the geometry of an interferometer allows one to construct the correlation functions from ideal negative measurements, which addresses the non-invasiveness requirement of the Leggett-Garg inequality. We discuss two concrete realisations of these ideas: the first in quantum Hall edge-channels, the second in a double quantum dot interferometer.

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Clive Emary, Neill Lambert, Franco Nori. 2012-10-09. The Leggett-Garg inequality in electron interferometers. https://doi.org/10.1103/physrevb.86.235447

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